论文标题
AL-LI相图的第一原理预测，包括配置和振动熵贡献
First principles prediction of the Al-Li phase diagram including configurational and vibrational entropic contributions
论文作者
论文摘要
从第一原理计算和统计力学中预测了整个AL-LI相图，包括配置和振动熵的影响。通过首先原理计算拟合的群集扩展，可以准确预测不同温度下不同配置的形成焓。每种构型的振动熵贡献是根据每种类型的键的键长与键刚度关系确定的，而不同相的Gibbs自由能是根据Monte Carlo模拟的温度而获得的。预测的相图与当前接受的实验相吻合，就其稳定（Alli，Al2Li3，Alli2，Al4li9）和亚稳态（AL3LI）阶段而言，它们之间的相位边界之间的相位界限和线相之间的最高稳定性温度。此外，它提供了有关AL3LI和Alli Solvus线之间差距的准确信息。最后，讨论了振动熵对相图正确预测的影响。总体而言，该方法表明，可以从第一原理计算中预测技术兴趣合金的准确相图。
The whole Al-Li phase diagram is predicted from first principles calculations and statistical mechanics including the effect of configurational and vibrational entropy. The formation enthalpy of different configurations at different temperatures was accurately predicted by means of cluster expansions that were fitted from first principles calculations. The vibrational entropic contribution of each configuration was determined from the bond length vs. bond stiffness relationships for each type of bond and the Gibbs free energy of the different phases was obtained as a function of temperature from Monte Carlo simulations. The predicted phase diagram was in excellent agreement with the currently accepted experimental one in terms of the stable (AlLi, Al2Li3, AlLi2, Al4Li9) and metastable (Al3Li) phases, of the phase boundaries between them and of the maximum stability temperature of line compounds. In addition, it provided accurate information about the gap between Al3Li and AlLi solvus lines. Finally, the influence of the vibrational entropy on the correct prediction of the phase diagram is discussed. Overall, the methodology shows that accurate phase diagrams of alloys of technological interest can be predicted from first principles calculations.
